DIFFERENCE OF GEOMETRIC MEAN

DIFFERENCE OF GEOMETRIC MEAN (LET)

Let Subcommand

Compute the difference between the geometric means for two response variables.

The geometric mean is defined as:

For the differeence of geometric means, the geometric mean is computed for each of two samples then their difference is taken.

LET <par> = DIFFERENCE OF GEOMETRIC MEAN <y1> <y2>                         <SUBSET/EXCEPT/FOR qualification>
where <y1> is the first response variable;
            <y2> is the first response variable;
            <par> is a parameter where the computed difference of the geometric means is stored;
and where the <SUBSET/EXCEPT/FOR qualification> is optional.

LET A = DIFFERENCE OF GEOMETRIC MEAN Y1 Y2
LET A = DIFFERENCE OF GEOMETRIC MEAN Y1 Y2 SUBSET X > 1

The difference of geometric means statistic is also supported for the following commands:
DIFFERENCE OF GEOMETRIC MEANS PLOT Y1 Y2 X
CROSS TABULATE DIFFERENCE OF GEOMETRIC MEANS PLOT Y1 Y2 X
BOOTSTRAP DIFFERENCE OF GEOMETRIC MEANS PLOT Y1 Y2
TABULATE DIFFERENCE OF GEOMETRIC MEANS Y1 Y2 X
CROSS TABULATE DIFFERENCE OF GEOMETRIC MEANS Y1 Y2 X
LET Z = CROSS TABULATE DIFFERENCE OF GEOMETRIC MEANS Y1 Y2 X1 X2


Enter

HELP STATISTIC PLOT
HELP CROSS TABULATE PLOT
HELP BOOTSTRAP PLOT
HELP TABULATE
HELP CROSS TABULATE
HELP CROSS TABULATE (LET)


for more information on these plots and commands.

None

None

GEOMETRIC MEAN	= Compute the geometric mean.
DIFFERENCE OF MEAN	= Compute the difference of means.
DIFFERENCE OF HARMONIC MEAN	= Compute the difference of harmonic means.
DIFFERENCE OF MEDIAN	= Compute the difference of medians.
DIFFERENCE OF TRIMMED MEAN	= Compute the difference of trimmed means.
DIFFERENCE OF MIDMEAN	= Compute the difference of midmeans.
DIFFERENCE OF BIWEIGHT LOCATION	= Compute the difference of biweight locations.
STATISTICS PLOT	= Generate a statistic versus subset plot.
CROSS TABULATE PLOT	= Generate a statistic versus two subsets plot.
BOOTSTRAP PLOT	= Generate a bootstrap plot.

Data Analysis

3/2003

SKIP 25 
READ IRIS.DAT Y1 TO Y4 X 
. 
LET A = DIFFERENCE OF GEOMETRIC MEAN Y1 Y2 
TABULATE DIFFERENCE OF GEOMETRIC MEAN Y1 Y2 X 
. 
XTIC OFFSET 0.2 0.2
X1LABEL GROUP ID
Y1LABEL DIFFERENCE OF GEOMETRIC MEANS
CHAR X 
LINE BLANK 
DIFFERENCE OF GEOMETRIC MEAN PLOT Y1 Y2 X 
CHAR X ALL 
LINE BLANK ALL 
BOOTSTRAP DIFFERENCE OF GEOMETRIC MEAN PLOT Y1 Y2 X  
    

Dataplot generates the following output.

       **************************************************
       **  LET A = DIFFERENCE OF GEOMETRIC MEAN Y1 Y2  **
       **************************************************
  
  
 THE COMPUTED VALUE OF THE CONSTANT A             =  0.27591226E+01
  
  
       *****************************************************
       **  TABULATE DIFFERENCE OF GEOMETRIC MEAN Y1 Y2 X  **
       *****************************************************
  
  
                 *    Y1       AND Y2
     X           *    DIFFERENCE OF GEOMETRIC MEANS
 **********************************************
     1.00000     *     1.58676
     2.00000     *     3.16211
     3.00000     *     3.60078
  
       GROUP-ID AND STATISTIC WRITTEN TO FILE DPST1F.DAT